octain level

if u put a octain level like 150 in ur car can that screw the engine up i did it once and i've never felt so much power from the car i had all 4 spinning. it was expensive but i thought it was worth it showing it off against my buddys wrx. i just wanna know if its worse having that kinda gas through the engine

[HighwayUFO]

Ok, not to sound like an A-hole, but you seriously need to clean up your typing. It hurts to read it. I don't recommend using anything much over 105 octane rating. I'm not sure who here has run or is running what octane, but 105 seems like a safe octane level to use in the engine.

Keith

[lee]

Can't say as I can answer your question, but you could do worse than reading the four-part FAQ starting here:

http://www.faqs.org/faqs/autos/gasoline-faq/part1/

[shoden]

Here's the part from that FAQ that kind of deals with your post:

6.13 Can higher octane fuels give me more power?

On modern engines with sophisticated engine management systems, the engine
can operate efficiently on fuels of a wider range of octane rating, but there
remains an optimum octane for the engine under specific driving conditions.
Older cars without such systems are more restricted in their choice of fuel,
as the engine can not automatically adjust to accommodate lower octane fuel.
Because knock is so destructive, owners of older cars must use fuel that will
not knock under the most demanding conditions they encounter, and must
continue to use that fuel, even if they only occasionally require the octane.

If you are already using the proper octane fuel, you will not obtain more
power from higher octane fuels. The engine will be already operating at
optimum settings, and a higher octane should have no effect on the management
system. Your driveability and fuel economy will remain the same. The higher
octane fuel costs more, so you are just throwing money away. If you are
already using a fuel with an octane rating slightly below the optimum, then
using a higher octane fuel will cause the engine management system to move to
the optimum settings, possibly resulting in both increased power and improved
fuel economy. You may be able to change octanes between seasons ( reduce
octane in winter ) to obtain the most cost-effective fuel without loss of
driveability.

Once you have identified the fuel that keeps the engine at optimum settings,
there is no advantage in moving to an even higher octane fuel. The
manufacturer's recommendation is conservative, so you may be able to
carefully reduce the fuel octane. The penalty for getting it badly wrong,
and not realising that you have, could be expensive engine damage.

To summarize, higher octane gas by itself doesn't increase power. It simply reduces the chance for pre-ignition (aka knock) and allows you to either raise the compression (by shaving the head, changing pistons, or a thinner gasket to name a few methods) or advance your timing (which the SVX does automatically, but I seriously doubt the engine management system is able to take advantage of 150 octane gas). It won't hurt your engine, but it won't help either, and it's basically a waste of money.

[ensteele]

I would doubt that you had all four tires spinning by just using 150 octane, unless it was in the gravel.

[nsm484]

Originally posted by ensteele
I would doubt that you had all four tires spinning by just using 150 octane, unless it was in the gravel.

And if he did... he'd probly be pricing a new tranny within say...
a month? heh.

[Alycone]

Hey, I had all four tires spinning with just 92 octane!









Okay, so all it meant was that my tires had no tread left and couldn't handle the Seattle rain.

[sharky512345]

all 4 tires are spinning every time i drive. they have to be for the car to move.




yea, i know im a smartass

[Hocrest]

Originally posted by sharky512345
all 4 tires are spinning every time i drive. they have to be for the car to move.

[n00b on demand]

Originally posted by sharky512345
all 4 tires are spinning every time i drive. they have to be for the car to move.




yea, i know im a smartass

haha

[Alycone]

Good point there!

Running a very high octane can cause damage in an engine thats not built to handle it. When you raise the octane level, you produce a fuel that burns slower. Meaning, that i will burn longer inside of the combustion chamber. For an engine with a long stoke or high compression, this is great. A short stroke or lower compression engine, this will lead to your valves scorching and your piston rings warping.
In the states, high grade fuel is rated at 91 oct. In japan and a good size chuck of the east this rating is kicked up to 98 oct. Better fuel there for some reason. o.O
So, to get the best bang for the buck, dump a bottle of octane boost in with your gas, and then your runing what the car was designed to run.

Run anything over 107 oct, and you run the risk of scorching or even melting vital componets in your engine, or at least, fouling your spark plugs realy quickly. Race engine can handle this due to the types of materals they use.

Hope this helps with your question

[dcarrb]

...and if it's leaded fuel, such as racing or aviation gas, it will foul catalytic converters.

Note item 8.1 in the FAQ: "What causes an empty fuel tank?"


dcb

I ran 110 octane in my car since I could get it for roughly $5/gallon and could afford it. What I can't afford now is the massive power loss I have and the fact that my car now BURNS a quart of oil every weeka and a half or so. Part of this might have something to do with the 160mph+ runs I was doing at the time, but it makes sense that slower burning gas would do bad things to your engine if it's not designed specifically for it.

On a happier note, I'm taking it into subaru for a $300 full inspection next month. Normally it would be $350 or so, but I work at a speed shop and get discounts and stuff. Yay for me.

[Mr. Pockets]

Originally posted by Da'Cheat
Meaning, that i will burn longer inside of the combustion chamber.

That's not exactly true. Higher octane gas just requires higher temperature and pressure to ignite spontaneously. It doesn't burn more slowly.